Twenty-two states -- but not Wisconsin -- are fighting back against an effort to change the traditional "one person, one vote" rule in a way that would limit legislative representative for minorities and children.

The US Supreme Court will hear arguments Tuesday in Evenwel v Abbot, a case that would change the generations-old interpretation of "one person, one vote" to include all people in a state, including those, such as children and non-citizen immigrants. Two Texas residents challenged that interpretation, arguing that only those who are eligible to vote should be considered in the rule.

If the court decides in favor of the plaintiffs, Wisconsin's congressional district populations would shrink dramatically, with the Milwaukee-based 4th District taking the hardest hit, according to socialexplorer.com. There are 710,873 people in the district, but just 479,802 are citizens of voting age. Some 26% of the total are children and 5.5% are non-citizens over 18, all of whom are ineligible to vote. The geographic size of the district would have to grow substantially if it were to include 520,125 potential voters, the ideal size under Evenwel.

Every other district in the state would be affected as well, though to lesser extents.

Twenty-one states, led by New York, filed a joint brief urging the court to leave the status quo in place. Besides New York, they include Alaska, California, Delaware, Hawaii, Illinois, Indiana, Iowa, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, New Hampshire, North Dakota, Oregon, Rhode Island, Vermont, Virginia, and Washington. Texas, where the case originated, continues to support existing interpretation of the rule.

The Brennan Center for Justice, in a brief description of the case, said that observers "have pointed out that it could potentially make it much more difficult to draw majority-minority districts if states were required to draw districts based on citizen voting population. They also note that, in addition to removing non-citizens, such a rule would exclude children and citizens who are simply not registered to vote. This exclusion, advocates for using total population argue, would be improper because children and noncitizen permanent residents still require constituent services from their elected officials and, as a result, excluding them would dilute their representation."